condyle

J Oral Maxillofac Surg66:77-84, 2008

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jointsThe majority of patients were male, and ranged from 5 to 52 years of age with a mean of 23 years.Twenty-five of 40 cases were the result of a sagittal fracture of the condyle, where the medial pole was

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doifractured off. Nineteen ankylosed joints (47.5%) showed lateral or superolateral displacement of thelateral aspect of the ramus/condylar process. Sixteen of 25 patients (64%) had fractures of the mandibleother than condylar fractures located in the anterior mandible that were often untreated or not properlyreduced. Fifty percent of the patients had widening of face or crossbites.

Conclusions: The results of this study indicate that the combination of an intracapsular fracture withconcomitant widening of the mandible leads to the lateral pole of the condyle or the condylar stump tobecome displaced laterally or superolaterally in relation to the zygomatic arch, where it fuses. Propertreatment of the anterior mandibular fracture(s) may help prevent the development of TMJ ankylosis insuch patients. 2008 American Association of Oral and Maxillofacial SurgeonsJ Oral Maxillofac Surg 66:77-84, 2008

mporomandibular joint (TMJ) ankylosis is one ofmost disruptive maladies that can afflict the mas-

atory system. The inability to move the mandibles significant functional ramifications, such as thebility to eat a normal diet. Additionally, speech isected, making it difficult for some individuals to

communicate and express themselves to others.When present in the young, growth disturbances ofthe face in general and the mandible specifically cre-ates facial asymmetries or severe mandibular deficien-cies (when bilateral) that are obvious even whenviewed from a distance. Dental care becomes impos-sible and the patient often suffers from dental pathol-ogy including dental caries and periodontitis. Prema-ture loss of the teeth is common with the inability forprosthetic replacement.

In addition to functional disturbances, there areintense psychologic burdens that patients with TMJankylosis must bear from the altered facial appear-ance, the difficulty of speaking and eating, and theinability to enjoy the fruits of the culinary arts.

Although the etiology of TMJ ankylosis is categorizedbroadly into infections and injuries, the propensity tothe development of TMJ ankylosis is not known. Themost striking finding in the literature concerning thistopic is the perceived frequency of ankylosis in some

Attending Surgeon, Peking University, School of Stomatology,

jing, China.

Professor of Oral and Maxillofacial Surgery, University of Texas

thwestern Medical Center at Dallas, Dallas, TX.

Professor, Department of Oral and Maxillofacial Surgery, Peking

iversity, School of Stomatology, Beijing, China.

Address correspondence to Dr Ellis: University of Texas South-

stern Medical Center at Dallas, Division of OMS, University of

as, 5323 Harry Hines Boulevard CS3.104, Dallas, TX 75390-

9; e-mail: [email protected]

008 American Association of Oral and Maxillofacial Surgeons

8-2391/08/6601-0013$34.00/0

:10.1016/j.joms.2007.08.013

77Etiology of TemporAnkylosis SecondFractures: The Ro

MandibulaDongmei He, DDS, MD, PhD,*

Yi Zhang, DD

Purpose: The purpose of the study was to explotemporomandibular joint (TMJ) ankylosis in a samp

Patients and Methods: All patients treated forPeking University, School of Stomatology, who hDemographic information and details of their originanalyzed by descriptive statistics.

Results: Twenty-five patients with 40 ankylosedandibular Jointy to Condylarof Concomitantracturesrd Ellis III, DDS, MS, and

D, PhD

e association between condylar fractures andm 1 hospital in China.

raumatic TMJ ankylosis in a 5-year period atfficient information available were included.ury and resultant ankylosis were tabulated and

met the inclusion criteria (15 were bilateral).

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78 TMJ AND FACIAL FRACTURESuntries, especially developing countries, and the rela-e scarcity of this disorder in developed countries.1

y would individuals in China, Africa, or India have aher incidence of TMJ ankylosis than individuals in theited States or Europe?Several possibilities exist that might explain thisference. First and foremost may be that there is notlly a higher incidence in developing countries. Itght be that because of the much greater populationdeveloping countries and more modern reportingchanisms, that the incidence is no different, evenugh the number of cases is more voluminous.If, on the other hand, there is an increased inci-nce, then one has to ask why. Is there a geneticedisposition to TMJ ankylosis among individuals inme countries? Are infectious arthritis and condylarctures, the factors linked most commonly to thevelopment of ankylosis, more common in thoseuntries? Is it possible that lack of ready access toalth care or poor treatment create the environmentwhich TMJ ankylosis can develop more readily?The purpose of this investigation was to examine aies of patients treated for TMJ ankylosis to deter-ne if there were any identifiable factors that mightpredisposing factors.

tients and Methods

The records of all patients who were diagnosedth traumatic TMJ ankylosis secondary to condylarctures at the Peking University, School of Stomatol-y, from January 2001 to August 2006, were re-wed. The diagnosis of ankylosis was made usingeral criteria, including inability to increase thendibular opening using physiotherapy before sur-ry combined with computed tomography (CT) ev-nce of bony fusion between the condylar processd the temporal bone, surgical findings of eitherrous or bony fusion between the condylar processd the temporal bone, or a combination of fibrousd bony fusion.The following information was collected from thedical record and tabulated: gender, age, cause ofuma, prior treatment, time between the injury andesentation to Peking University, and mouth open-

(interincisal dimension). The occlusion, facialmetry, and facial width were determined by re-wing the photographs that were available on alltients. Of particular interest was the presence of assbite and widening of the face (unilateral vs bilat-l).All patients had coronal and axial CT scans takenfore surgery to treat the ankylosis and some had 3Dreconstructions available. Data obtained from thescans were condyle fracture type (intracapsular vstracapsular, horizontal fracture through the head ofcondyle vs sagittal splitting of the condyle), posi-n of the ramus stump or hemicondyle in relation-ip to the glenoid fossa, associated mandibular frac-es, and width of the mandibular arch.The type of TMJ ankylosis was recorded from sur-ry as being fibrous, fibro-osseous, or osseous. Thesition of the articular disc was also recorded fromsurgical findings.

sults

Twenty-five patients with TMJ ankylosis had suffi-nt information available from their medical recordinclusion in this study. There was a large genderference, with 19 males and only 6 females. Thees ranged from 5 to 52 years with a mean of 22.6ars. The traumatic injury included falls (n 11), carshes (n 8), motorcycle crashes (n 4), indus-al (n 1), and blast injury (n 1). Thirteen pa-nts (52%) had treatment of their fracture(s) at an-er facility before presentation for treatment ofkylosis. Patients presented for treatment of theirkylosis anywhere from 6 weeks to 7 years afterury (mean, 20.2 mo). Ten patients had unilaterald 15 of the patients had bilateral TMJ ankylosistal 40 TMJ). All cases of ankylosis were associ-d with a fracture of the mandibular condyle.According to the CTs, the most common type ofndyle fracture (n 25/40 joints) was a sagittallitting where the medial pole was detached andplaced (usually anteromedially) but the lateral poles still attached to the ramus (Fig 1). The next mostmmon injury (n 12/40 joints) was a horizontalcture of the condylar process at a high level (intra-

URE 1. Computed tomography scan showing bilateral sagittaltures of the mandibular condyle with medial pole dislocation,ening of the intercondylar distance, and superolateral movement oflateral pole of the condyle.

, Ellis, and Zhang. TMJ and Facial Fractures. J Oral Maxillofacg 2008.

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HE, ELLIS, AND ZHANG 79psular). In 3 joints it was impossible to determinetype of fracture of the condyle the patient had

stained because there was a solid mass of bonyion between the mandibular ramus and the cranialse. The stump of the ankylosed mandibular ramuss positioned within the confines of the articularsa in 21 patients (52.5%). Nineteen ankylosednts (47.5%) showed lateral or superolateral dis-cement of the lateral aspect of the ramus/condylarocess. Sixteen of 25 patients (64%) had fractures ofmandible other than condylar fractures. In each ofse cases, the additional fracture(s) was located inanterior region of the mandible. The ability to

en the mouth varied between 0 to 25 mm, with aan of 11.3 mm. Two patients had documentedssbites, and 11 had obvious widening of their facecumented on clinical exam (Fig 2). During surgery,ankylosed joints were categorized as bony, 8 asrous, and 3 as fibro-osseous. The disc was locatedteromedially in every case.

scussion

The most interesting finding of this study popula-n was the high association of ankylosis with sagittalctures of the mandibular condyle. The Americanthors experience is strikingly dissimilar to thisdys and warnings in literature that sagittal frac-es of the condyle with the medial pole being dis-ced anteromedially are prone to osteoarthrosis2 orJ ankylosis.3 Such condylar process fractures inr unit (Dallas) are treated by benign neglect. Theact lateral pole provides vertical and horizontalpport to the mandible so the only treatment neces-y is allowing the patient to function. No case ofJ ankylosis resulting from sagittally split condyless been seen in patients treated at Parkland HospitalDallas, TX, whereas many cases have occurred inPeking University sample. One has to wonder,refore, if there is something else that predisposesch fractures to the development of ankylosis.The information presented in Table 1 may hold they to this query. Sixteen patients with TMJ ankylosisd concomitant fractures in the anterior mandibled most of these were associated with superolaterallateral displacement of the lateral pole of the sag-lly-split condyle. Most of these patients (13/16)o presented with widening of the mandibular archt was reflected in the occlusion or the width of the

URE 2. Frontal (A) and submental (B) views of a patient withteral ankylosis showing widening of the face in the preauriculargonial angle regions from malreduction of symphysis fracture.


Table

PatientNo.

1

234

567

8

910

1112

13141516171819202122

232425

N 25

Abbrevfixation; R

He, Ellis,801. TWENTY-FIVE CASES OF POST-TRAUMATIC TMJ ANKYLOSIS

GenderAge(yr) Etiology

Time BetweenInjury andPresentation

With AnkylosisMouthOpening

AnkylosisType

Condylar FxLocation and

Type

Relationship ofRamus Stump toArticular Fossa

AssociatedMandibular Fx

Prior Treatmentof Fx

Mandibular Archor FacialWidening

M 27 MCA 2 mo 15 mm Fibrous Bi-head Rt-superolateral, Ltin fossa

Symph (linear) Y Symph fx Y (cross bite)

M 17 MVC 2 mo 10 mm Fibrous Bi-sagittal Bi lateral dislocation Symph (linear) Y Symph fx Y (cross bite)F 38 MVC 1.5 mo 18 mm Fibrous Bi-sagittal Bi superolateral Symph (linear) Y Symph fx Y (face wide)M 49 MCA 2 mo 10 mm Fibrous Rt-sagittal Superolateral Body (linear) Y Body fx Y (R-angle

prominent)M 52 IND 2 mo 15 mm Fibrous Bi-head Bi superolateral Symph (linear) Y Symph fx Y (face wide)M 20 Fall 4 mo Fibrous Bi-sagittal Bi lateral dislocation Symph (comminuted) N Y (face wide)M 31 MVC 1.5 yr Fibrous Bi-sagittal Rt-lateral dislocation

Lt in fossaSymph (comminuted) Y Symph fx Y (Lt-angle

prominent)F 13 MCA 5 mo 15 mm Fibrous Bi-sagittal Rt-superolateral

Lt in fossaBody (linear) Y Body fx Y (face wide)

M 11 Fall 2 mo 10 mm Fibro-osseous Bi-sagittal Bi in fossa None N NF 19 MVC 6 mo Fibro-osseous Rt-sagittal Superolateral Body (linear) Y Body fx and

ORIF Ltsubcondylarfx w/wire

Y (Rt ramusprominent)

M 25 Fall 3 mo 25 mm Fibro-osseous Bi-sagittal Bi superolateral Symph (linear) Y Symph fx Y (face wide)M 36 MVC 7 mo 20 mm Bone Rt-sagittal Superolateral Symph (linear) Y Symph fx Y (Rt ramus

prominent)F 18 MVC 2.5 yr 10 mm Bone Rt-sagittal In fossa Symph (linear) Y Symph fx NoM 37 MCA 7 yr 12 mm Bone Bi-sagittal Bi in fossa None No NoM 5 Fall 5 mm Bone Lt-head In fossa None No NoM 8 Fall 1 y 0 Bone Bi-head Bi in fossa None No NoM 12 Blast 2 yr 5 mm Bone Lt-head In fossa Body (linear) No NoM 9 Fall 4 yr 12 mm Bone Bi-head Bi in fossa Symph (linear) Y Symph fx NoF 8 Fall 3 yr 10 mm Bone Lt-Sagittal In fossa None N NoM 5 Fall 3 yr 13 mm Bone Lt-head In fossa None N NoM 22 Fall 4 mo 5 mm Bone Lt-Sagittal In fossa None N NoF 28 Fall 3.5 yr 20 mm Bone Lt-mass, Rt-

sagittalRt in fossa Lt

superolateralBody (linear) N Y (left face

wide)M 6 Fall 8 mo 5 mm Bone Lt-head In fossa None N NM 31 MVC 3 yr 0 Bone Bi-bone mass Bi in fossa Symph (linear) N NM 37 MVC 6 yr 13 mm Bone Bi-sagittal Bi superolateral Indeterminate Y ORIF both

cond fx withwire

Y (face wide)

M 19F 6

5-52Avg 22.6

Falls 11MVC 8MCA 4Blast 1IND 1

1.5 mo-7 yrAvg 20.2

mo

0-25 mmAvg

11.3

Fibrous 8Fibro-osseous 3

Bony 14

40 sides:Sagittal 25Head 12Bone mass 3

In fossa 21Superolateral 14Lateral 5

Associatedmandibular fx 16

Y 13N 12

Cases ofincrease inmandibulararch/facialwidth 13

iations: Avg, average; Bi, Bilateral; fx, fracture; IND, industrial; Lt, left; MCA, motorcycle accident; MVC, motor vehicle (non-motorcycle) collision; N, no; ORIF, open reduction internalt, right; Symph, symphysis; TMJ, temporomandibular joint; Y, yes.

and Zhang. TMJ and Facial Fractures. J Oral Maxillofac Surg 2008.

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HE, ELLIS, AND ZHANG 81e. Some of these patients had had treatment of theterior mandibular fractures immediately after injuryother facilities (13/16 patients), but it was obviousexamining the patients when they presented foratment of their ankylosis that the surgery to restorendibular arch form was inadequate in most (11/13tients treated for their associated mandibular frac-e) (Fig 3).The locations of the ankylosis in these patientsre largely between the raw edge of the condyle (inlocation where the medial pole used to be) withlateral and inferior aspect of the zygomatic arch

g 4). The lateral pole of the condyle was laterally orperior laterally located, indicating that the treat-nt of the symphyseal or body fracture(s) was inad-uate (Figs 3, 5). For a condyle to be located lateralthe mandibular fossa, 1 of 2 things had to havecurred. Unilateral lateral dislocation could occuren without other mandibular fractures but in suchses the opposite condyle would have to be posi-ned medially. This is unlikely and was not seen inr sample. It could also occur with bilateral condylarctures with no other fractures elsewhere in thendible, but did not occur in our sample for the 3ateral cases of condyle fracture not associated with

URE 4. Intraoperative photograph showing fusion of the laterale of the superolaterally-displaced condyle with the zygomatic arch.

, Ellis, and Zhang. TMJ and Facial Fractures. J Oral Maxillofacg 2008.URE 3. Posteroanterior skull radiograph (A) and submental 3D CTn showing bilateral condylar fractures combined with symphysisture that was treated inadequately, resulting in widening of thee. Note the gap on the lingual aspect of the symphyseal fracturege arrow) resulting in widening of the mandible and inter-ramusth (small arrows).


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82 TMJ AND FACIAL FRACTURESother fracture in the mandibular arch. None ofse 3 patients had a combination of lateral displace-nt on 1 side and medial displacement on the other.e other method by which lateral or superior dislo-tion of the lateral pole of the condyle can occur isthe mandibular arch width to have increased. Thisuld require another fracture of the mandible and ineping with the data from our sample, this is foundmmonly and located in the anterior mandible/25 patients; 64%). An associated fracture in theterior mandible has also been consistently presentcases of lateral displacement of mandibular con-les, even without ankylosis.3

The above observation that ankylosis can occur withagittally-split condyle that is laterally or superolaterallyplaced is not new. In 1982, Rowemade the followingservation: In both the adult and the older child therean inadequately recognized cause of ankylosis that ise to an anteroposterior split of the condyle. Theeral fragment passes upward over the outer rim of thenoid fossa and the inner pole, to which the lateralrygoid muscle is attached, is displaced antero-medi-. The associated displacement of the intra-articularc, and the accompanying loss of mobility, frequentlymbine to produce an ankylosis.1 Nothing was men-ned about the presence of other fractures of thendible, but for the lateral pole of the condyle to besitioned over the outer rim of the glenoid fossa, it isely that other fractures in the anterior portion of thendible that allowed widening of the mandible weresent.The association with TMJ ankylosis after traumath other fractures of the mandible is rarely dis-ssed in the literature but there has been somention of associated fractures but never has there

URE 5. Intraoperative photograph showing a symphysis fracturene of the ankylosis cases that was not reduced properly, resultingidening of the face and intercondylar region.

, Ellis, and Zhang. TMJ and Facial Fractures. J Oral Maxillofacg 2008.en any association between the other fractures anddevelopment of ankylosis. Bear and Tankersley4

orted a case of an 11-year-old female who wasolved in a bicycle accident and was treated for ain laceration. It was later noted she had a leftndibular body fracture and a right condylar neckcture that progressed to TMJ ankylosis. Similarly, ineview of lateral condylar displacements even in thesence of ankylosis, Rattan3 found all cases wereociated with symphyseal fractures.In describing the characteristics of 81 ankyloticnts in 56 patients, Norman and Bramley mentioned,. . a number were bilateral and associated with arasymphyseal fracture and a period of unduly pro-ged intermaxillary fixation.5 In the description ofradiographic findings, it was also mentioned, In

me instances exuberant bone will extend from theeral aspect of the mandible to the adjacent zygo-tic arch.5 Unfortunately, there was no mention ofether those with bone bridging laterally betweenramus and zygomatic arch were those that had

ncomitant parasymphyseal fractures.There are a few other reports of a similar pattern ofseous fusion in some TMJ ankylosis cases. Swah-y6 described 4 forms of TMJ ankylosis and his typeis one where there is a bony bridge from the ramusthe mandible to the zygomatic arch. There was nontion of other associated mandibular fractures int report. A similar pattern of osseous fusion wasscribed by Aggarwal et al.7

Based on the results of our study and the sparseormation in the literature on this topic, one couldt forth the following hypothesis for the develop-

URE 6. Illustration showing the proposed mechanism of ankylosisany of the patients. The articular disc displaces medially along

h the medial pole of the condyle. When the symphysis fracture iser not reduced or inadequately reduced, the mandible widensows), allowing the lateral pole of the condyle or ramus stump toome displaced superolaterally. It then becomes in direct contacth the bone of the zygomatic arch, where it fuses.


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HE, ELLIS, AND ZHANG 83nt of some cases of traumatically induced TMJkylosis (Fig 6):

1. Fracture of the mandibular condyle (especiallysagittal intracapsular fractures).

2. Associated fracture of the body or symphysis ofthe mandible.

3. No or inadequate reduction of associated frac-ture(s) leading to an increase in the intercondy-lar distance (or inter-ramus distance at the levelof the stump).

4. Fractured surface of residual ramus or lateralpole of condyle displaces laterally and possiblysuperiorly to the glenoid fossa. As noted in thisstudy, the articular disc is displaced anteromedi-ally and is no longer interposed between thefractured fragment of the ramus or lateral poleof the condyle and the zygomatic arch. Studieshave shown that damage to the articular surfaceor removal of the disc are necessary conditionsfor the formation of TMJ ankylosis in an animalmodel.8-13 Laskin14 considers that the most im-portant feature in a fracture encouraging anky-losis is close contact between the glenoid fossaand the condylar stump. The conditions foundin our study are therefore ideal for ankylosis.

5. Mandibular hypomobility. This could result from1 of 3 mechanisms:a. Patient not seeking treatment and not moving

jaw voluntarily because of pain. This wasnoted by Worthington15 who listed hypomo-bility as one sign of lateral condylar displace-ment;

b. Inability to move jaw from other conditions(ie, head injury, mechanical restriction fromlateral displacement of condyle or impinge-ment of coronoid process on zygomaticarch); or

c. Treatment using a period of maxillomandibu-lar fixation (MMF). This would allow initialhealing between the fresh fractured end ofthe ramus or lateral pole of the condyle withthe zygoma.

Although it is impossible to prove this hypothesism the data presented, the data is certainly consis-t with this mechanism in a large percentage ofses. If this hypothesis is accurate, it indicates thatatment should be directed toward properly reduc-the fractures in the body/symphysis regions of thendible to attain the correct intercondylar distance.is, by itself, should prevent lateral displacement ofhemicondyle or ramus stump so that it is unlikely

move superiorly, over the outer rim of the glenoidsa where it can fuse to the zygoma. Obviously, theer basic tenet of treating intracapsular condylarctures must also be used. These patients should beowed full unrestricted function of their mandibleshelp prevent organization of the intracapsular he-toma that likely occurs. A review of the literaturelateral dislocations of the condyle suggested that

ch a relationship can lead to fibrosis and ankylosis.3

Although there are many possible reasons why de-loping countries have an increased number of pa-nts presenting with ankylosis, the most plausiblean increased incidence of condylar fractures and

availability of appropriate care for patients. Theidence of condylar fractures in China has beenorted to be between 30.7% and 33% of all mandib-r fractures,16-18 which is not different from therld literature.19-23

If an increase incidence in condylar fractures can-t be implicated, then perhaps the unavailability ofoper care may be an important factor in the largembers of TMJ ankylosis seen in developing coun-es. The data in this study may hold a key to whyre are seemingly many more cases of TMJ ankylosisdeveloping countries than in more developed ones.e access to health care is much more limited inveloping countries so mandibular fractures may nottreated at all. Even the patients in our study whoeived treatment for their body or symphysis frac-e before presenting with ankylosis were notated adequately. Most had under-reduced fracturesthe anterior mandible. This left the intercondylartance too great, resulting in laterally or superolat-lly displaced condyles, wide faces, or crossbites.e reason that so many of these patients had under-uced fractures is that they were often treated atilities where the surgeon had little experience intreatment of facial fractures. It is unclear but

obable that inexperience may have also led to longriods of MMF. Thus, whether the problem was nore or inadequate care, the development of TMJkylosis may have been in part, iatrogenic.

ferencesRowe NL: Ankylosis of the temporomandibular joint. J R CollSurg Edinb 27:67, 1982Wu XG, Hong M, Sun KH: Severe osteoarthrosis after fractureof the mandibular condyle: A clinical and histologic study ofseven patients. J Oral Maxillofac Surg 52:138, 1994Rattan V: Superolateral dislocation of the mandibular condyle:Report of 2 cases and review of the literature. J Oral MaxillofacSurg 60:1366, 2002Bear SE, Tankersley RL: Bilateral ankylosis and hyperplasia ofthe mandibular condyles after mandibular fractures: Report ofcase. J Oral Surg 29:451, 1971Norman JE deB, Bramley P: Ankylosis, in Textbook and ColorAtlas of the Temporomandibular Joint. Ipswich, England,Wolfe Medical Publications, 1990, pp 154-155Swahney CP: Bony ankylosis of the temporomandibular joint:Follow-up of 70 patients treated with arthroplasty and acrylicspacer interposition. Plast Reconstr Surg 77:29, 1986

7. Aggarwal S, Mukhopadhyay S, Berry M, et al: Bony ankylosis ofthe temporomandibular joint: A computed tomographic study.Oral Surg 69:128, 1990

8. Miyamoto H, Kurita K, Ogi N, et al: The role of the disk in sheeptemporomandibular joint ankylosis. Oral Surg 88:151, 1999

9. Miyamoto H, Kurita K, Ishmaru JI, et al: A sheep model fortemporomandibular joint ankylosis. J Oral Maxillofac Surg 57:812, 1999

10. Miyamoto H, Kurita K, Ogi N, et al: The effect of an intraartic-ular bone fragment in the genesis of temporomandibular jointankylosis. Int J Oral Maxillofac Surg 29:290, 2000

11. Miyamoto H, Kurita K, Ogi N, et al: Effect of limited jaw motionon ankylosis of the temporomandibular joint of sheep. Br J OralMaxillofac Surg 38:148, 2000

12. Matsuura H, Miyamoto H, Ogi N, et al: The effect of gaparthroplasty on temporomandibular joint ankylosis: An exper-imental study. Int J Oral Maxillofac Surg 30:431, 2001

13. Oztan HY, Ulusal BG, Aytemiz C: The role of trauma on tem-poromandibular joint ankylosis and mandibular growth retar-dation. An experimental study. J Craniofac Surg 15:274, 2004

14. Laskin DM: Role of the meniscus in the etiology of posttraumatictemporomandibular joint ankylosis. Int J Oral Surg 7:340, 1978

15. Worthington P: Dislocation of the mandibular condyle into thetemporal fossa. J Maxillofac Surg 10:24, 1982

16. Bao B, Gu XM, Zhou SX, et al: Clinical retrospective study of1693 facial trauma patients. Hua Xi Kou Qiang Yi Xue Za Zhi16:56, 1998

17. Zou LD, Zhang Y, He DM, et al: A retrospective study of 1084facial fractures. China J Oral Maxillofac Surg 1:131, 2003

18. Li YS, Tian WD, Li SW, et al: [Retrospective analysis of 3,958patients with facial injuries]. Zhonghua Kou Qiang Yi Xue ZaZhi 41:385, 2006. Chinese

19. Ekholm A: Fractures of the condyloid process of the mandible.Suom Hammaslaak Toim 57:9, 1961

20. Rowe NL, Killey HC: Fractures of the Facial Skeleton (ed 2).Edinburgh, E&S Livingstone, 1968, p 234

21. Tasanen A, Lamberg MA: Transosseous wiring in the treatmentof condylar fractures of the mandible. J Maxillofac Surg 4:200,1976

22. Olson RA, Fonseca RJ, Zeitler DL, et al: Fractures of the man-dible: A review of 580 cases. J Oral Maxillofac Surg 40:23, 1982

23. Ellis E, Moos KF, El-Attar A: Ten years of mandibular fractures:An analysis of 2,137 cases. Oral Surg 59:120, 1985

84 TMJ AND FACIAL FRACTURES

Etiology of Temporomandibular Joint Ankylosis Secondary to Condylar Fractures: The Role of Concomitant Mandibular FracturesPatients and MethodsResultsDiscussionReferences

Documents

condyle